Duplex pump.



c, M. CHURCH.

DUPLEX PUMP.

APPLICATION FILED AUG.16. i913.

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C. M. CHURCH.

DUPLEX PUMP.

APPLICATION FILED AUG. I6, 1913.

1,1 64,169. Patented Dec. 14, 1915.

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DUPLEX PUMP.

I APPLICATION FILED AUG. 16. 19I3. 1,164,169. Patented Dec. 14, 1915.

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' 06mm. M. 651 16 f MQ J sraus CLARENCE M. CHURCH, OF ARNOLD, PENNSYLVANIA.

DUPLEX PUMP.

Specification of Letters Patent.

Patented Dec; 1 1, 1915.

Application filed August 16, 1913. Serial No. 785,109.

To all whom it may concern.

Be it known that I, CLARENCE M. CHURCH, a citizen of the United o'tates, and a resident of Arnold, in the county of WVestmoreland and State of Pennsylvania, have invented a new and "useful Improvement in Duplex Pumps, (Case B 5) and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to pumps and particularly to that class known as duplex pumps wherein two or more cylinders are operated by steam or other fluid for the purpose of operating the pumps and it is the principal object of my invention to improve upon pumps of this character.

My inventionconsists, generally stated, in the novel arrangement, construction and combination of parts as hereinafter more specifically set forth and described and particularly pointed out in the claims.

To enable others skilled in the art to which my invention appertains to construct, operateand use my improved duplex pump I will describe the same more fully referring to the accompanyingdrawings in which Figure 1 is top plan view of the ordinary duplex pump embodying my invention.

Fig. 2 is a side elevation of the same showing one of the operating cylinders in section. Fig. 3 is an enlarged detail view of the valve device showing its operation in connection with one of theoperating cylinders. Fig. 4: is a like view of the valve device showing its operation in connection with the other operating cylinder. Fig.5 is a top view of the engaging members. Fig. 6 is a side view of the same. Fig. 7 is a partial view of the one side of the pump showing a modification. Fig. 8 is a like view on the other side of the pump. Fig. 9 is a top plan view of the same.

Like symbols of reference herein indicate like parts in each of the 'figures of the drawings. 7

As illustrated in the drawing my improved pump is provided with two cylinders but there may be any even number of the same although a single duplex pump is shown on the drawings in order to avoid complications in the same and in the description.

The pump -is provided with a pair of pump cylinders 1 and 2 which are located parallel to each other. and contain the ordinary pumping parts (not shown) which parts are operated by piston rods 3 and a respectively which extend into said cylinders from operating cylinders 5 and 6 located parallel to each other at the other end of the pump. Within the operating cylinders 5 and 6 are the pistons 7 and 8 which are sev cured to the ends of the piston rods 3 and 1 respectively and are controlled by the valves 9 and 10 respectively in the valve casings 11 End 12 located above said operating cyliners.

The valve casingll has the usual ports 13 and 13 for admit-ting operating fluid to the cylinder 5 and for allowing such fluid to exhaust through said ports and into an exhaust port 1 1 formed in the upper wall 15 of said cylinder and in the lower face of the valve 9. The valve 9 is provided with a valve stem 16 which extends outward from the valve casing 11 and into slide bearings 17 on the rock shaft stand 18. This rock shaft stand 18 is supported between the cylinders 1 and 5 and the cylinders 2 and 6 upon a suitable support 19 extending between said cylinders and carries arock shaft 20 at its upper end and a rock shaft 21 at its lower end as later explained. At the one end of the rock shaft 20 is a small rock arm 22 secured firmly thereto and pivotally connected at its outer end with a pair of engaging members 23 and 23 which rest upon a fiat portion of the valve stem 16 while at a po sition on said valve stem less than the distance between the outer ends of said members are the lugs 24: and 24? as later explained. Behind the valve stem 16 and located at a distance slightly greater than the distance between the outer ends of the members 23 and 23 are a pair ofsmall trip rolls 25 and 25 respectively which can be adjusted longitudinally as desired in order to increase or decrease the distance between the same. These trip rolls 25 and 25 are adapted to rotate idly on their respective centers and their periphery extends slightly above and slightly below the upper and lower face of the valve stem 16, and lugs thereon as later explained,

The rock shaft 21 is provided with along rock arm 26 which is securely mounted thereon while one end of the same extends slightly above said shaft and is provided with the pivoted engaging members 27 and 27* which bear against the lower flat face of the valve stem 16. The lower face of the valve stem 16 is also provided With a pair of lugs 28 and 28 which are spaced on said valve stem at a distance slightly less than the distance between the outer ends of the members 27 and 27 as "the outer ends of said members as near as possible to the fiat sides of the valve stem 16. The other end of the long rock arm 26 extends downward and is pivotally mounted in a cross head 32 which is securely mounted on the'piston rod 3 in order to rock the said arm when said piston is set in motion.

At the other side of the pump and as shown in Fig. 4: the va ve casing 12 has the usual ports, one of which is indicated at 33, for admittingoperating fluid such as'steam to the cylinder 6 and for allowing the said fluid to exhaust through said ports and into an exhaust port 14c in the upper wall 15 of said cylinder and the lower face of the valve 10. This valve 10 is provided with a valve stem 16 which extends outward from the valve casing 12' and into slidebearings 17 on the rock shaft stand 18. The end of the rock shaft 21 on this side of the 'pump is provided with a small rock arm 34 '35 and 35 which are pivoted thereto and rest upon the flat lower face of the valve stem 16. The lower face of the valve stem 16 is provided with a pair of lugs 36 and 36 which are spaced on said valve stem at a distance slightly less than the distance between the outer ends of the engaging members 35 and 35 as later explained.

Behind valve stem 16' is a pair of idle rolls 37 and 37 which can be adjusted longitudinally asdesired in order to increase or decrease the distance between the same as later explained. These trip rolls 37 and 37 are adapted to rotate idly ontheir respective centers and their periphery extends below the under face of the valve stem 16' and the lugs 36 and 36 as later explained. The rock shaft 20 on this side of the pump is provided witha long rock arm 37 which is securely mounted thereon, while one end of the same extends slightly above the said shaft and is provided with a pair of engaging members 38 and 38 pivoted thereto. These engaging members 38 and 33? are adapted to rest upon extensions 39 and 39 on the upper face of the valve stem 16" and each of the'same is Provided with a lug 40 and 40 respectively which are spaced on said extensions at a distance slightly less than the distance between the outer ends of the engaging members 38 and 38 Behind each of the extensions 39 and 39 is a small trip roll 41 and 41* respectively which can be adjusted longitudinally as desired in order to increase or decrease the distance between the same as later explained. These trip rolls etl and tl are adapted to rotate idly on their respective centers and their periphery extends above the top of the extensions 39 and 39 and thelugs 4'0 and 4:0 thereon as later explained; p 7

The engaging members 35 and 35 and the engaging members 33 and 33' are each provided with a. flattened end 29 which tapers from a shoulder 30 and between each of the said pairs of members a spring 31 rests against said shoulders in order to keep the outer flattened ends 30 as near possible to the valve stem 16. The other end of the long rock arm 37 extends downward and is pivotally mounted in a cross head 4.2 which .n

is securely mounted on the piston rod 4 in order to rock the said arm when said piston is set in motion. j V

The use and operation of my improved pump is as follows :Considering the one side of the pump in the position shown in Figs. 2. and 3 with the valve 9 in the position where the operating fluid will enter through the port "13 and press thepiston '7 forward and at the same time exhaust the waste operating fluid from the other side of the'same' through the ports 13 andllet. As

the piston moves forward in the cylinder the long rock a1'n1'26 is also moved forward and thus rocks or rotates the rock shaft 21 while the engaging members 27 and 27 will be moved along the'v alve stem 16 until the former strikes against the lug 28 which usually occurs when the piston 7- has completed about half of'its stroke although this may be adjusted as desired as the shaft 3 continues to move forward the valve stem 16 is pushed toward the rear and the valve 9 is operated so asto close the ports 13 and 13 whereupon the flattened end 29 of engaging member 27 will strike the trip roll 25 which will raise it from its engagement with the lug 28 so that the said'valve will be left in this position. As the ports 13 and 13 are closed the operating fluid behind the piston 7 will expand to complete the stroke while the waste fluid in front of suchpiston will be compressed in order to form a cushion for such piston and thus prevent any jarring.

While this operation just above described .has been going on the rock shaft 21 has been turning and moving the engaging members 35 and 35 backward and during the first half approximatelyv of the stroke of the piston 7 the engaging members 35 will have taken up its lost motion and rest against the lug 36 on thevalve stem 16. As the member 35 strikes the lug 36 it pushes the valve ing members 23 and 23 backward and durtated the shaft 20 by the long rock arm 37 and moved the engaging members 38 and'38 forward so that when about half the piston stroke had been accomplished the flattened end 29 of the member 33 having taken up all its lost motion would strike the lug to 011 the extension 39 and thus draw the valve stem forward to close both the ports 33 and 33 The operating fluid which entered through the port 33 will expand to complete the stroke while the fluid on the other side of the piston will be compressed to form a cushion so as to prevent any jarring.

While the piston 8 has been operating the rock shaft 20 the small arm 22 on the other side of the pump will have moved the engaging about the first half of the stroke of said piston the member 23 will be taking up lost motion whereupon it strikes the lug 24: on the valve stem 16 and pushes the same backward thus operating the valve 9 to open the port 13 to' operating fluid and the port 13 to the exhaust port 14. At this point the flattened end 29 of the engaging member 23 will strike the trip roll 25 thus raising said member from its engagement with the lug 24. During this time the shaft 3 has been moving backward and while the piston 7 has been completing about half of its stroke the said shaft has been operating the long rock arms 27 and 27 forward to take up the lost motion between the member 27 a and the lug 28 About the time the piston 7 reaches the middle of its stroke the member 27* engages with the lug 28 and moves the valve stem forward thus operating the valve 9 to close the ports 13 and 13 while the flattened end 29 of the member 27 will strike against the trip roll 25 and raise the same from its engagement with the lug 28 and thus leave both the ports 13 and 13 in a closed position.

WVhile the shaft 3 has been moving forward it has rotated the shaft 21 and the small rock arm 3st on the other side of the pump and the engaging members 35 and 35 have been moved forward the former taking up lost motion during the first half of the stroke of the piston 7 and striking the lug 36 on the valve stem 16 when the stroke of said piston is about half completed. As the member 35 thus strikes the lug 36 the valve stem 16 is moved forward and the valve 10 small shaft t6.

opens the port 33 to the operating fluid and said member from its engagement with the lug 36 as shown in Fig. 41.

Figs. 7, 8 and 9 show a modified construction wherein the trip rolls 25", 25, 41, and 4-1 for operating a single pair of engaging members on each side of the pump are mounted on rods 43 and 4-3 which rods are pivotally mounted on the rock shaft stand 18 and such rods are pivotally connected at their upper ends to rods 4% and 44: respec tively while the ends of said last named rods are pivotally connected one to each end of link members 455 which are securely fixed to a This shaft 46 has an arm t? which connects with a governing means, which is usually a Mason regulator, whereby such shaft is turned in order to change the position of the trip rolls 25 and 25 and the trip rolls ell and 41 to regulate the cut off in the cylinders 5 and 6.

It will thus be seen that with the use of my improved apparatus the cut-off may be effected at any desired point in the piston stroke and practical experience and demonstration has shown the same to be much more efficient than the present constructions.

What I claim as my invention and desire to secure by Letters Patent is 1. In a pump, a pair of cylinders, pistons in the cylinders, piston rods for the pistons, valves controlling the admission and exit of the motor fluid for the cylinders, valve stems for the valves and a valve operating mechanism, said mechanism including a pair of shafts, a pair of rock arms operatively connecting the opposite ends of the two shafts with the piston rods, and movable members yieldably held in engagement with the valve stems for actuating the same upon movement of the piston rods.

2. In a pump, a pair of cylinders, pistons in the cylinders, piston rods for the pistons, valves controlling the admission and exit of the motor fluid for the cylinders, valve stems for the valves and a valve operating mecha nism, said mechanism including a pair of shafts, a pair of rock arms operatively connecting the opposite ends of the two shafts with the piston rods, and movable members yieldably held in engagement with the valve stems for actuating the same upon movement of the piston rods, certain of said movable members being pivotally attached to the shafts and certain other of said movable members being pivoted to and controlled by said rock arms.

3. In a pump, a pair of cylinders, pistons in the cylinders,- piston rods for the pistons,

valves controlling the admissionand exit of the motor fluid for the cylinders, valve stems for the valves, and a valve operating mechanism, said mechanism including a pair of shafts, a pair of rock arms operatively connecting the opposite ends of the two shafts with the piston rods, lugs carried on'the valve rods, pivoted engaging members carried by each shaft at opposite ends, pivoted engaging members carried by each of said rock arms, and yieldable means normally holding all of said engaging members in position against the valve stems for engaging the lugs thereon upon the movement of the piston.

4. In a pump, a pair of cylinders, pistons in the cylinders, piston rods for the pistons,

valves controlling the admission and exit of the motor fluld for the zcyllnders, valve stems for the valves, and a valve operatmg mechanism, said mechanism including a pair of shafts, a pair of rock arms operatively connecting the opposite ends of the two shafts with the piston rods, lugs carried on the valve rods, pivoted engaging members carried by each shaft at opposite ends, pivoted engaging members carried by each of said rock arms, and yieldable means normally holding all of said engaging members in position against the valve stems for engaging the lugs thereon upon the movement of the piston, and rotatable means for automatically and synchronously moving the several engaging members into inoper ative relation to the lugs.

5. In a pump, a pair of cylinders, pistons in the cylinders, piston rods for the pistons,

valves controlling the admission and exit of the motor fluid for the cylinders, valvestems forthe valves, and a valve operating mechanism, said mechanism including a pair of shafts, a pair of rock arms operatively con- 7 necting the opposite ends of the two shafts with .the piston rods, lugs carried on the valve rods, pivoted engaging members carried by each shaft at oppositeends, pivoted engaging members carriedby each of said rock arms, and yieldable 'means normally holding all of said engaging members in position against the valve "stems forengaging' CLARENCE M. CHURCH.

Witnesses T. B. HUMPHRIEs, J; W. MAYFIELD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner offatents- Washington, D. C. 

